A Guide to Scuba Diving in the Florida Keys

There are many excellent diving sites in the world; however, one of the most impressive lies at the southern tip of Florida. The Florida Keys are an archipelago of over 800 islands spanning roughly 125 miles, connected by 42 bridges along the Overseas Highway.

The Florida Keys have long been a popular tourist destination, and one of the major reasons is the quality and variety of diving available, with the Keys supporting the third largest barrier reef in the world.

When planning a diving trip for the Florida Keys, there are many options of places to see including reefs and wrecks. 

The Keys are typically divided into three major geographical areas: the Upper Keys, Middle Keys, and Lower Keys. Let’s take a look at some of the highlights of each area.

I’ve just returned from a few days diving so this article comes while everything is fresh in mind. All photos taken for this article were from my trip.

The Upper Keys

The Upper Keys is the first area you’ll encounter if you’re driving into the chain of islands from the mainland. You’ll enter the Keys on the Overseas Highway (or Card Sound Road if traffic is bad) and arrive in Key Largo. 

Currently, the Upper Keys likely serve as the best sites for reef diving as they were largely spared from damage from Hurricane Irma.

The major communities of the Upper Keys are Key Largo, Islamorada, and Tavernier. 

Key Largo is known as the Dive Capital of the World while Islamorada is known as the Sport Fishing Capital of the World. The Upper Keys have a large area and lots of mangroves.

Things to Do (Besides Diving)

• Snorkeling at John Pennekamp State Park (the U.S.’s first undersea preserve)
• Feed the tarpon or grab some food at Robbie’s of Islamorada
• Kayak out to the Indian Key ghost town
• Visit the History of Diving Museum
• Meet a dolphin at Theater of the Sea

Dive Sites

Molasses Reef

For those who favor coral reefs, Molasses Reef is by far the favorite of many Keys locals. With depths ranging from 20 feet to over 100 feet, Molasses Reef has canyons of coral reefs and several swim-throughs.

It is a great place for sea turtles, nurse sharks, angelfish, and even an occasional pelagic visitor. 

On my last dive there, we encountered a hammerhead. In fact, the photos on this blog are all from a recent trip to Molasses Reef. You’ll easily find several boats each day that go to the area.

Christ of the Abyss

This site located in John Pennekamp Park is a 10-foot replica of a much larger statue from Italy. It is located in 25 feet of water and presents a fun photo opportunity. You’ll find the site near Dry Rocks reef which may prove to be an excellent second stop.

The Duane and Bibb

These are a pair of U.S. Coast Guard cutters that were sunk as part of an effort to create artificial reefs. Both ships are 327 feet in length. The Duane is the more popular site, sitting upright in 100 feet of water. The Bibb sits completely on her side at 120 feet.

Both ships served in the Vietnam War and World War II. The Duane helped sink a German submarine and was also later a part of the Mariel Boat Lift. Both wrecks are excellent places for wahoo, amberjacks, and goliath grouper. These sites are heavily fished, so divers typically want to check them out early in the day.

Eagle

Another excellent wreck, the Eagle was a Dutch freighter that was intentionally sunk in 1985. It lies near Islamorada, just off of Lower Matecumbe Key. It is well known for its large mast assemblies and its propeller. The ship is first encountered at 65 feet of depth and sits on an angle down to 110 feet.

Hurricane Georges split the Eagle in half, providing easy access to the inside of the ship. This wreck is an excellent location for catching tarpon, goliath grouper, snook, spotted eagle rays, and barracuda.

Spiegel Grove

The Spiegel Grove is one of the most impressive dive sites in the Florida Keys. This wreck of a Navy docking ship sits at 80 feet and is massive at 510 feet in length. The ship actually encountered a problem during sinking and sunk too soon, landing on her side. However, Hurricane Dennis knocked it back upright, where it sits today.

Located on Dixie Shoal off of Key Largo, the Spiegel Grove has a number of features including an old gun mount and an American flag. It can have a strong current at times as well. 

Over 125 species have been documented including a resident goliath grouper, snapper, bluehead wrasse, and ocean surgeonfish.

The Middle Keys

The Middle Keys begin after leaving Islamorada and consist of Key Vaca and Grassy Key as well as a number of smaller islands. The major area here is Marathon, a town over ten miles long (but not very wide) that is the second largest in the Keys.

The Middle Keys is also home to the iconic Seven Mile Bridge. It likely has fewer diving sites than other areas of the Keys but is known for a number of impressive ones.

Things to Do (Besides Diving)

• Visit Pigeon Key National Historic District
• Watch rescue and rehabilitation efforts at Turtle Hospital
• Kayak through Curry Hammock State Park
• Checkout the Florida Keys Aquarium
• Visit Dolphin Research Center

Dive Sites

Coffins Patch

A few miles east of Key Colony Beach lies Coffins Patch, a reef where divers can view boulder coral, pillar coral, spiny lobsters, and moray eels. In total, there are six different patch reefs that comprise Coffins Patch.

The depth is relatively low, ranging from 10 to 40 feet, many that this area is excellent for divers with only an open water certification. Additionally, this area has an easy current making it excellent for divers of any skill level.

Sombrero Reef

Another excellent site for divers of any level, Sombrero Reef is one of the most beautiful reefs in the Keys. It features a wide variety of coral including pillar coral, brain coral, lettuce coral, and gorgonian coral.

Located roughly eight miles off of Vaca Key and distinguishable by Sombrero Key Lighthouse, this reef has depths ranging from 10 to 35 feet. Typical sights include angelfish, barracuda, and the ever-curious moray eels.

Thunderbolt

For wreck lovers, the Thunderbolt is the must-see in the Middle Keys. Part of the Florida Keys Shipwreck Trail, it served in World War II and was sunk in 1986. It sits between 85 and 120 feet, is intact, and relatively easy to explore, making it one of the more friendly wrecks for those new to wreck diving.

Divers to the Thunderbolt will likely encounter a number of different species. It is popular for large schools of barracuda as well as angelfish and jacks. A variety of corals and sponges can also be found at the site.

The Lower Keys

The Lower Keys extend from No Name Key to Key West and feature Big Pine Key. The Lower Keys are islands that are short and wide in comparison to the route of the Overseas Highway.

Things to Do (Besides Diving)

• Checkout the beach at Bahia Honda State Park, once honored as world’s best beach.
• Try to spot the tiny Key Deer on Big Pine Key (and drive slowly … they’re endangered)
• Grab pizza at No Name Pub on Big Pine Key
• Visit iconic Key West establishments like Sloppy Joe’s and Capt. Tony’s
• Visit the Shipwreck Museum
• Visit Hemingway House and Museum and meet the famous polydactyl cats
• Stop by for a late-night dessert at Better Than Sex (you’ll need a reservation)

Dive Sites

Adolphus Busch

Located off of Big Pine Key, the Adolphus Busch was a British cargo ship. At 210 feet long, it sits in 110 feet of water. Only three dive shops visit the ship, meaning that you won’t worry about crowds.

This wreck was sunk purposefully in a manner to make it safe for light penetration or the cargo hold. Looking into portholes will find green moray eels while the site tends to be popular with stingrays as well.

Looe Key

Due south of Ramrod Key, this five square mile protected ecosystem likely competes with Molasses Reef for the best reef in the Keys. Although damaged by Hurricane Irma, a dive boat captain recently informed me that it has bounced back fairly well.

Looe Key is an excellent site to visit with depths ranging from 7 to 30 feet. Since Looe sits on the edge of the barrier reef, it is a prime spot to see larger fish in addition to typical reef inhabitants. Tarpon, large rays, and a variety of sharks can often be seen. In fact, I’ve saw several tarpon every time I’ve been to Looe.

Vandenberg

The most popular wreck in the Lower Keys, the Gen. Hoyt S. Vandenberg is a former troop transport and missile tracking ship that is 522 feet in length. It currently sits in 140 feet of water; however, at ten stories high, the structure can be accessed from 40 feet below the surface.

The Vandenberg is a massive ship and sports the iconic Conch Republic flag as well as a large satellite dish. Those with training in light wreck penetration can experience a large amount of the ship through hulls cut into the hull and a few swim-throughs.

Joe’s Tug

This wreck has a bit of a mystery with it. This is a 75-foot shrimp boat that initially sunk in Key West Harbor. She was recovered and prepared for scuttling but was stolen and sank seven miles southeast of Key West.

The wreck was heavily damaged by Hurricane Georges. Her bow and stern now sit roughly 30 feet apart. The ship does sit upright, and the wheelhouse is easily accessible. This is a popular site for underwater photographers including Elvis, the resident goliath grouper.

Final Thoughts

The Florida Keys are a beautiful island chain with lots to do. From the nightlife of Key West to the laid back vibe of Islamorada, there are many sights and sounds to checkout.

For divers, the Keys are a cornucopia of adventure. The third largest barrier reef system in the world stretches over 200 miles and has excellent sites for a wide array of wildlife.

For those in search of wrecks, particularly those with advanced open water certification, the Keys is home to over 1,000 shipwrecks including lots of well-known intact ships.

Additionally, the Keys has a plethora of dive operators. Anyone heading will want to do their research to find their ideal dive outfit. Popular ones include Rainbow Reef, Captain Slate, Amoray Resort, Key Dives, and Islamorada Dive Company.

An additional benefit of the Keys is that the water is suitable for diving year-round. In February (the coldest month), you just need a 3 mm or 5 mm wetsuit while most of the year you’ll only need a rash guard or maybe a shorty.